80c51

Other chips in the same family

Number	notes
80C31	ROMless
80C51	4k x 8 ROM
83C751	2k x 8 ROM
87C51	4k x 8 EPROM
87C751	2k x 8 EPROM

8-bit Microcontroller

Pinout

DIP40
           +---\/---+
      P1.0 | 1    40| Vdd
      P1.1 | 2    39| P0.0/AD0
      P1.2 | 3    38| P0.1/AD1
      P1.3 | 4    37| P0.2/AD2
      P1.4 | 5    36| P0.3/AD3
      P1.5 | 6    35| P0.4/AD4
      P1.6 | 7    34| P0.5/AD5
      P1.7 | 8    33| P0.6/AD6
       RST | 9    32| P0.7/AD7
  RxD/P3.0 |10    31| *EA/Vpp
  TxD/P3.1 |11    30| ALE/*PROG
*INT0/P3.2 |12    29| *PSEN
*INT1/P3.3 |13    28| P2.7/A15
   T0/P3.4 |14    27| P2.6/A14
   T1/P3.5 |15    26| P2.5/A13
  *WR/P3.6 |16    25| P2.4/A12
  *RD/P3.7 |17    24| P2.3/A11
     XTAL2 |18    23| P2.2/A10
     XTAL1 |19    22| P2.1/A9
       Vss |20    21| P2.0/A8
           +--------+

Frequency

DIP40
Set reader to FREQ, put black probe to GND, red probe to 18 and 19 to measure CPU clock

External links

80C51 page on Wikipedia
80C51 page on CPU-World

Files

• 

  80C51 Datasheet

• 

  87C750 Datasheet